Hemingway was rejected for regular military service in World War I because of a weak left eye, so he drove a Red Cross ambulance in Italy, distributing chocolate to Italian troops. While recuperating from serious wounds in a Red Cross hospital in Milan, Hemingway fell in love with nurse Agnes von Kurowsky, who later rejected him as too young. These World War I experiences eventually became invaluable fodder for his most famous war novel, A Farewell to Arms. The experiences contributed to many of his war novels' recurring themes: the cruelty and stupidity of war, the greedy materialism and quest for power that cause war, the platitudes and abstractions that glorify war, and the value of enduring whatever must be endured.
As a foreign correspondent for the Toronto Star Weekly, Hemingway moved to Paris. Armed with a letter of introduction from Sherwood Anderson to Gertrude Stein, Hemingway established friendships with a number of famous expatriate writers who helped him develop his craft. Hemingway published In Our Time, a collection of short stories, some of them the Nick Adams stories set in Michigan. In 1923, Hemingway made the first of five consecutive yearly trips to Pamplona, Spain, for the bullfights — an experience that eventually served as a basis for The Sun Also Rises, which is about the expatriate life in Paris and Pamplona. In the epigraph of that book, Hemingway quotes a line that Gertrude Stein previously recounted: "You are all a lost generation." The phrase "lost generation" quickly became a mantra of the post World War I generation's attitude about the war's effect on their lives and the futility and meaninglessness of life.
